Influence of a new monomerio nonionic radiographic contrast medium (Iobitridol-350 versus NaCl) on cutaneous microcirculation: Single-center, prospective, randomized, double-blind phase IV study in parallel group design

This single-center, prospective, randomized, doubleblind phase IV study wit h parallel-group design was performed to test whether injection of a newly designed non-ionic monomeric radiographic contrast medium in the axillary a rtery influences the ipsilateral cutaneous microcirculation. Twenty patient s with coronary heart disease or suspected coronary heart disease were inve stigated. Ten patients received iobitridol and 10 normal saline solution. T he confirmatory target variable was the capillary erythrocyte velocity (v(R BC)). The v(RBC) was continuously recorded before and up to 3 min after the inj injection of iobitridol or normal saline solution and subsequently eva luated off-line. Thirty seconds after injection of 20 ml iobitridol, v(RBC) was reduced by 32% (P < 0.05). This was the strongest reduction, but v(RBC ) was reduced at all time points measured up to 180s following the injectio n (P < 0.05 up to 180 s). The overall reduction in V-RBC was also statistic ally significant (P 0.0446). In contrast, there was a tendency toward an in crease in v(RBC) following injection of 20 ml normal saline (P 0.0512). The re was also a tendency toward a difference in the time course of changes in v(RBC) following injection of iobitridol compared to normal saline (P 0.06 07). The decrease in v(RBC) following iobitridol injection (standardized di fference (SD) according to Cohen, 0.67) can be regarded as biometrically we ak, and the increase following normal saline injection (SD, 0.24) as very w eak. The microcirculatory disturbance induced by iobitridol injection is le ss severe than that due to comparable high-viscosity contrast media. (C) 20 00 Academic Press.